The invention relates to foamed epoxies, and more particularly, to foamed epoxies prepared using an anhydride additive in the presence of a tertiary amine catalyst.
Foamed epoxies are normally produced via addition of physical blowing agents such as inorganic compounds that thermally decompose at low temperatures and produce gases, or via addition of low volatile liquids, such as freons or similar fluorinert compounds, that also result in gas formation during the exothermic epoxy cure. In comparison, polyurethanes are commonly cured using an in-situ chemical side reaction that produces gaseous CO2 during the cure reactions. This reaction is specific to the properties of isocyanates, the key molecular building block of polyurethanes. Due to the completely different type of epoxy curing reaction, an in-situ chemical foaming process similar to the standard and widely used polyurethane foaming reactions and process has so far not been described in the literature.